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Rolling-element bearings are the most commonly used components in all rotating machinery. The variations in the operating conditions such as an increase in the number of operating cycles, load, speed, service temperature, and lubricant degradation result in the development of various defects such as pitting, spalling, scuffing, scoring, etc. The defects that appeared on rolling contact surfaces cause surface deterioration and change in the vibration and sound levels of the bearing system. The present experimental investigations are aimed at assessing the surface fatigue wear that appears on the contact surfaces of roller bearings. The studies considered the estimation of specific film thickness, analysis of surface fatigue wear developed on the rolling-element surfaces, surface roughness analysis, grease degradation analysis using Fourier transform infrared radiation, and vibration and sound signal measurement and analysis. The results obtained from the experimental investigation provide a good correlation between surface wear, vibration, and sound signals with a transition in the lubrication regimes in the Stribeck curve.

Upper limb arterial access is being increasingly used for coronary diagnostic and intervention procedures. Radial artery access is associated with reduced morbidity and mortality as compared to femoral artery access. However, access to the radial artery is not always successful with reported crossover rates to other routes between 3% and 8%. Ulnar artery access is emerging an attractive option both as upfront access and rescue access in case of failure to obtain radial artery access.

In the present paper, some results on a Lorentzian Sasakian manifold endowed with a quarter-symmetric metric connection have been studied.

This paper contributes to the ongoing research on measuring the industrial development at a micro (district) level and turning the findings into useful policy tools. The paper takes the analysis at micro level and concentrates on the districts of Jharkhand state – one of the most resource rich states in India with a low level of industrial development. For better understanding the impact, the infrastructure is split into three major components – physical infrastructure (PI), banking infrastructure (BI) and social infrastructure (SI). Results show that, when all the districts as a group is considered, for all the models, the association of the components of infrastructure with level of industrial development is found to be weak – which reflects the low level of infrastructure availability in the state, whereas when the more industrialised districts are considered, for the same set of models, only PI and SI are found to be significant, suggesting a lack of proper synchronisation of the industrial development policy for BI at the district level.

The paper investigates the causal nexus among financial development, social development, and economic growth for 15 Asian countries for the period 1961–2011. Using the Granger causality test, both at the individual country and at the panel settings, the results suggest that (1) financial development and social development generally lead to economic growth; (2) the Granger causality from financial development to economic growth and from economic growth to financial development coexists; (3) the Granger causality from social development to economic growth and from economic growth to social development coexists; and (4) the Granger causality from financial development to social development and from social development to financial development coexists. The findings are, however, not uniform; it varies from country to country and from region to region.

The paper investigates the causal relationships between penetration rate, an indicator of telecommunications development, and economic growth of 34 OECD countries during the period 1960–2010. The panel model is used in this study. Based on the panel cointegration test results, is found that penetration rate has a long run relationship with economic growth. Moreover, there is also a bidirectional Granger causality between penetration rate and economic growth in both the short run and long run. The results of this study show clearly that telecommunications development plays an important role in the economic growth of the OECD countries. Furthermore, these results can reinforce the importance of economic growth for the continued development and use of various telecommunications services in those countries.